how can I get firefox to save a changed password to a site. email@example.com
I had to change password that firefox saved.
Open Tools -> Options or, if that option isn't there, Edit -> Preferences and select Security from the resulting window. Click Saved Passwords, which will open a dialog box with all the sites you have passwords saved on. Click the site your password changed on, and choose Remove. The next time you go to that site and input your password, you'll be asked if you want to save your password. Press Yes and it'll save your new password.